Solid State Preamp Reviews

Setup
Unlike the problems I experienced with the first Krell KSA-250 power amplifier review sample, installation of the KBL went without a hitch. Although I preferred to place the KBL atop the stereo cabinetry, Puffin the Pouncer (a very large domestic longhair cat) seemed to enjoy sleeping on the KBL; my visions of exploding preamps in the night forced a move to a lower, less cat-able location (footnote 1). Unlike many preamps that I have owned or auditioned, the KBL's rear panel is very clearly labeled; connections can be easily accomplished with an angled dentist's mirror. The "blind finger-touch and plug-in technique" can also be performed, because there's lots of room between all inputs and outputs (unlike those damn female Camac receptacles crowded together at the rear of the Levinson No.26). Experimentation showed that the power supply is best located at least a foot away from the preamp module, and power cords can indeed improve sonic performance.

So far, of all four AC cables auditioned—original Belden supplied with the preamp, Distech Power Bridge II, Music and Sound cable, and Tiffany power cable—the Tiffany seems to do the best job. Overall sonic presentation with the Tiffany is more open and dynamic than the other three, and soundstage is definitely more natural. Dan D'Agostino has more than once made it perfectly clear to me that he doesn't believe in sonic witchcraft (neither do I), and that fancy power cables don't necessarily sound better, just different. This time, however, it really does sound much better (footnote 2). Placing three Sumiko Navcom Silencers underneath the KBL (two in the rear, one in front center) also appears to significantly improve clarity and soundstage depth. It's interesting that these devices don't do very much for the Esoteric and Krell CD drives I've been auditioning, or my Levinson No.26 preamp.

Similar to other high-end preamps, the KBL takes a significant amount of time to reach sonic potential—in this case, four weeks. Listening during the first week was a waste of time. "Dull, cloudy, and covered" would be the best way to describe out-of-the-box performance. Over the next three weeks, frequency extension at both extremes began to expand, as well as soundstage dimensionality and dynamic impact. Although the manufacturer claims that serious listening can be done after a few days, my experience would suggest otherwise. Patience, I'm afraid, is a necessary ingredient with this product. (How many audiophiles do you know who can count patience among their virtues?)

Sonic philosophies...
In my review of the Krell KSA-250 power amplifier (January 1991, Vol.14 No.1), I came to the conclusion that, while the Levinson No.23 power amp could be sonically more engaging in some circumstances, the Krell bettered its competition in overall musical honesty. That same parallel can be drawn between the KBL and No.26 preamps. In absolute musical accuracy, the Krell clearly surpasses the Levinson on most counts. But the No.26 offers an alluring perspective that may well appeal to the listener who prefers highly vivid harmonic textures and impressive soundstage depth over an absolutely correct replica of the musical material. While the No.26 unquestionably gives a warmer, more richly colored sonic picture, the KBL supplies the listener with a more musically honest, but possibly less sonically exciting view of the performance.

This does not imply, however, that one is necessarily "better" than the other. Rather, these differences between two very good products suggest a clear divergence of sonic philosophies which may or may not appeal to the individual listener. Yes, in my opinion, the Krell supplies more of what actually went on during the recording session (footnote 3). For a musician, this is of utmost importance. But the microphone does not interpret musical performances in the same manner as the human ear, and the Krell's deadpan reflection of this may prove to be unrewarding, even irritating to some people.

As with any exceptional audio product, two planes of discussion diverge re. the KBL's performance: purely sonic parameters and musical accuracy. Sonically, the KBL follows Krell's signature of smoothness, top-to-bottom coherence, clarity, and incredible dynamic punch. At first casual listen, this preamp does not appear to have as wide or deep a soundstage as the Levinson No.26. But first impressions are not necessarily valid, and extended audition of the KBL vs the No.26 suggests that the No.26's deeper, wider perceived soundstage remains constant with all program material (similar to many tube products), placing a definite sonic stamp on every performance. The No.26 is also, subjectively, easier on the ears. There's a greater sense of space and ambience surrounding the musicians, along with a softening of all instrumental and vocal attacks.

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Footnote 1: There's a famous story about the cat who liked to perch atop a certain person's Eagle 7 amplifier. One day, plagued by an indigestible hairball, the cat barfed into the amplifier, and the whole thing blew up, launching the unfortunate feline across the room.

Footnote 2: In fact, the Tiffany power cables also work wonders for the Krell KSA-250, KMA-300, Mark Levinson Nos.23 and 23.5 amplifiers, as well as the Levinson No.26 preamp. And speaking of witchcraft, I've got to tell you about a gizmo I picked up at last January's Las Vegas CES. It's manufactured by Coherent Systems, and is called "Electraclear, Model EAU-1." You're supposed to plug this contraption into the same AC mains serving your audio equipment (just like all those other "clocks" you've been reading about), with resultant sonic improvement. I hate to admit it, but this thing actually works; in fact, darn well. I won't dwell on specifics right now, but even my non-audiophile colleagues in the National Symphony who think all this high-end audio mania is total nonsense were impressed by the musical improvements this black box delivered.

Footnote 3: I qualify this by referring to recordings in which I and my colleagues have performed.